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BACKGROUND: Fresh ginseng is typically accompanied by soil after harvest, leading to contamination with harmful fungi during storage and distribution. In this study, we investigated the incidence of fungal contamination in fresh ginseng (5–6 years old) purchased from 22 different stores in Geumsan, Korea. RESULTS: The incidence of fungal contamination in the samples was 67.4–111.5%. Fusarium solani was the most abundant species in the head (38.5%) and fine root (19.3%) parts of the ginseng samples, whereas F. oxysporum was the most abundant in the main root (22.0%) part. We isolated Aspergillus, Fusarium and Penicillium spp. (total number of isolates: 395) from the ginseng samples, and 138 isolates were identified using phylogenetic analysis. Polymerase chain reaction‐based screening of 65 mycotoxin‐producing species revealed that two P. expansum isolates were positive for citrinin and/or patulin, and five F. oxysporum isolates were positive for fumonisin biosynthesis gene. One P. expansum isolate produced 738.0 mg kg−1 patulin, and the other produced 10.4 mg kg−1 citrinin and 12.0 mg kg−1 patulin on potato dextrose agar (PDA) medium. Among the 47 representative F. oxysporum isolates, 43 (91.5%) produced beauvericin (0.1–15.4 mg kg−1) and four of them (8.5%) produced enniatin B and enniatin B1 (0.1–1.8 mg kg−1) as well. However, none of these toxins was detected in fresh ginseng samples. CONCLUSION: Fusarium solani and F. oxysporum were the most abundant species in fresh ginseng samples. Most F. oxysporum (43) and P. expansum (2) strains isolated from fresh ginseng produced beauvericin and enniatins (B and B1), and patulin or citrinin, respectively, on PDA medium. This is the first report of the mycotoxigenic potential of P. expansum and F. oxysporum strains isolated from fresh ginseng. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

This study investigated the fungal diversity in ginger from fields and storage and the effects of storage temperature and relative humidity (RH) on fungal and mycotoxin occurrence. A total of 909 isolates from ginger samples (30 from fields and 24 from storages) were identified using a molecular approach. Fusarium (23 species, 82.3%) was dominant in the ginger samples, followed by Aspergillus (16 species, 8.5%), and Penicillium (11 species, 2.1%). Among the Fusarium species, F. oxysporum (28.3%) was predominant, followed by F. asiaticum (14.9%) and F. solani (7.2%). Most isolates of F. oxysporum , F. graminearum, and F. fujikuroi species complex tested produced the respective mycotoxins: beauvericin (15.9–93.4 mg/kg), nivalenol (16.0–611.6 μg/kg), deoxynivalenol (31.3–1605.5 μg/kg), and fumonisins (0.1–101.4 mg/kg) on potato dextrose agar. During six months of ginger storage under three conditions, Fusarium species predominated (64.8%), followed by Aspergillus (3.8%) and Penicillium (0.1%). The frequency of F. oxysporum increased during storage, whereas mycotoxin occurrence varied significantly depending on storage conditions (p < 0.05). At 5 °C/73% RH, F. oxysporum frequency was the lowest (32.8%), while the average concentrations of enniatins were the highest (2030.0 μg/kg). At 14 °C/68% RH, F. oxysporum frequency (71.9%) and beauvericin (725.7 μg/kg) were the highest. At 13 °C/96% RH, F. oxysporum frequency (56.1%) was lower than at 14 °C/68% RH, and beauvericin (56.8 μg/kg) and enniatins (41.3 μg/kg) were the lowest. Aflatoxins and ochratoxin A were not detected in any of the stored samples. These results suggest that 13 °C/96% RH is the most suitable storage condition for ginger to minimize fungal growth and the production of mycotoxins. • Fusarium oxysporum was the dominant fungus in both fresh and stored ginger samples. • Fusarium species isolated from ginger produced beauvericin on potato dextrose agar. • Minimal occurrence of mycotoxins was observed when ginger was stored at 13 °C and 96% relative humidity. [ABSTRACT FROM AUTHOR]